<!-- 
  inline标签vsblock标签
  行标签的特点
  1.不会换行
  2.宽度由内容决定

  块标签的特点
  1.占满整行
  2.宽度就是容器的宽度

  块标签: div h1-h6 p form......
  行标签: span img a......
 -->
 <!DOCTYPE html>
 <html lang="en">
 <head>
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>块标签和行标签</title>
 </head>
 <body>
   <h1 style="border: 2px green solid;">
     块标签不会和任何标签摆在一行
   </h1>
   <p style="border: 2px green solid;">
     Lorem ipsum, dolor sit amet consectetur adipisicing elit. 
     Neque mollitia aperiam veritatis quam illo quos. 
     Ea, quam natus neque omnis explicabo sunt totam molestiae exercitationem iusto ipsa nihil ut expedita.
   </p>
   <!-- 文本内容本质上是一个行标签属性 -->
   

   <a href="#" style="border: 2px green solid;">行标签的长度根据内容来定</a>
 </body>
 </html>